1 // SPDX-License-Identifier: GPL-2.0 2 /* console.c: Routines that deal with sending and receiving IO 3 * to/from the current console device using the PROM. 4 * 5 * Copyright (C) 1995 David S. Miller (davem@davemloft.net) 6 * Copyright (C) 1996,1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz) 7 */ 8 9 #include <linux/types.h> 10 #include <linux/kernel.h> 11 #include <linux/sched.h> 12 #include <asm/openprom.h> 13 #include <asm/oplib.h> 14 #include <linux/string.h> 15 16 static int __prom_console_write_buf(const char *buf, int len) 17 { 18 unsigned long args[7]; 19 int ret; 20 21 args[0] = (unsigned long) "write"; 22 args[1] = 3; 23 args[2] = 1; 24 args[3] = (unsigned int) prom_stdout; 25 args[4] = (unsigned long) buf; 26 args[5] = (unsigned int) len; 27 args[6] = (unsigned long) -1; 28 29 p1275_cmd_direct(args); 30 31 ret = (int) args[6]; 32 if (ret < 0) 33 return -1; 34 return ret; 35 } 36 37 void prom_console_write_buf(const char *buf, int len) 38 { 39 while (len) { 40 int n = __prom_console_write_buf(buf, len); 41 if (n < 0) 42 continue; 43 len -= n; 44 buf += len; 45 } 46 } 47